What Can We Expect From Teenage NBA Rookies?

When looking at incoming NBA rookies, there's always the question of how quickly a player should contribute. If a player starts off fast – like Michael Carter-Williams did last year, for example – is that a sign of future stardom or merely the NBA not adapting to his game yet? On the other hand, if a player starts off slow, when is the time for panic and when is the time for patience?

These are the questions that fans wonder every year, especially as their team trots out their next “franchise cornerstone” they drafted with a lottery pick. In order to gather some realistic expectations, let’s first establish a ceiling.

To clarify, this article will only examine data for players who were teenagers at the time of their first season. Most players above that threshold have played multiple years of college basketball and we can already see definable traits and how they will contribute to the NBA. Plus, a majority of the great NBA superstars came into the league in their teenage years, so there’s that.

In order to set a ceiling, I used Basketball Reference's Season Finder to figure out how out how teenage NBA players have performed in the past. I restricted my search to find players who were teenagers in their rookie season and posted at least five win shares.

If you’re wondering what a good win share total is, for reference, 89 players hit the 5.0 or higher mark this past season. All-Star caliber players are generally 7.0 or higher (41 players hit that mark this past season). The superstars – the All-NBA caliber – are usually 10.0 or higher. In total, 15 players hit that mark this season.

When I initially did my search, I put a low number (5.0 WS) and was expecting to have to raise the parameters. However, I only got five players back. Here they are.

In case you were wondering, there were two players from last season that were eligible for this list – the Bucks' Giannis Antetokounmpo and the Sun’s Archie Goodwin. They had 1.2 and 0.2 win shares, respectively. A player like Goodwin drafted at the end of the first round won’t have much opportunity their rookie season, so that can possibly skew some results. Although, it is incredibly rare for a star-caliber player to come from that range anyway.

Last year’s draft class was significantly older than this year’s, as shown by only having two teenage rookies this past season. Here’s a list of players drafted in the first round who will still be a teenager this season: Andrew Wiggins, Jabari Parker, Aaron Gordon, Dante Exum, Noah Vonleh, Zach LaVine, James Young, and Bruno Caboclo.

Of those players, all but Vonleh and Caboclo should get extensive minutes during this first year, if not an outright starting spot. So what should we expect? Well, we should probably expect some pretty steep learning curves.

Some final observations...

All of the five above are frontcourt players. Expanding the parameters to 4.0 win shares or more as a teenager, we only get four extra teenagers – Andre Drummond, Thaddeus Young, Kevin Garnett, and Kyrie Irving. Only one guard. It seems like the learning curve for guards is steeper than young big men.

To affirm this, last year’s Rookie of the Year, Michael Carter-Williams, had a RPM (Real Plus-Minus) of -3.05. That included a DRPM of -2.10. Coming into the NBA as a rookie and having to guard the likes of Chris Paul, Russell Westbrook, John Wall, and so on…that’s tough.

All of the five listed above are considered five of the world’s best players, if not future Hall of Famers. So, this is something to watch this season – if one of our rookies can hit that mark, it bodes very well for their future.

Part of the reason why the best players have historically performed well at a young age is because they got drafted at a young age. The best prospects come out early because they are going to be early picks. It goes the other way for prospects who don't rate as highly - they're more inclined to try to improve their draft stock prior to declaring.

This isn’t about the incoming rookies, but Anthony Davis had the highest PER of any teenage rookie ever. He’s going to be a superstar.

To keep on this tangent, Drummond missed our win share mark (he had 4.5 as a rookie), but was just 0.1 below Davis in regards to PER, and ahead of the other guys in the table above.